PB, Greivious had some tricky assemblies around the neck that you have to pay attention to, but other than that, he fell together quite well. I do suggest gluing his outer armor pieces down if you plan to handle him as they can (and will) fall off.
As for the blaster, how can you even ask? I have taken on the whole rebellion while making the pew, pew sounds. It is just to fun. I would suggest getting at least one, I have my eye on the Han Solo blaster next. The blaster is all put together, I am just trying to do a good job on painting and weathering right now.
Bish, no worries! You have a lot on your plate. Yep I got the blaster from across the pond and it sounds like you found the same seller. I would have to say the casting came from a sterling as it had a lot of the machine stamps on it. This really builds into a nice prop.
-Stephen